Loxjie D30 DAC and Headphone Amplifier Review

[Atanasi]

A grounded power supply, USB input and RCA output seems like a dangerous combination with respect to ground loops.

 

[gvl]

A grounded power supply, USB input and RCA output seems like a dangerous combination with respect to ground loops.

External brick, ground loop or electrocution, choose your poison.

 

[ninetylol]

A grounded power supply, USB input and RCA output seems like a dangerous combination with respect to ground loops.

I only use Dacs with separate power, so i dont have to connect them to the PC USB. Put DAC and amp into same ground and GG.

 

[Tips]

Yeah, it would be great to see LDAC and Apt-X HD measured too.
What about measuring Airplay though Amir please?
It should have much higher performance than any Bluetooth right?

 

[RickSanchez]

Yeah, it would be great to see LDAC and Apt-X
HD measured too.
What about measuring Airplay though Amir please?
It should have much higher performance than any Bluetooth right?

I don't see any indication that the D30 supports Airplay or Airplay2: http://loxjie-audio.com/productshow.asp?id=156

 

[somy]

Looks like BT has a long way to catch up

 

[Toku]

I don't see any indication that the D30 supports Airplay or Airplay2: http://loxjie-audio.com/productshow.asp?id=156

You can check all devices that support Airplay & Airplay 2 on Apple's HP.
There are no Chinese products there.

 

[Deleted member 18309]

I'm a little confused, the documentation only mentions aptX and SBC for Bluetooth support, but Amir managed to do a test with AAC? Does that mean AAC is also supported by the D30 but the documentation doesn't say?

 

[Veri]

I'm a little confused, the documentation only mentions aptX and SBC for Bluetooth support, but Amir managed to do a test with AAC? Does that mean AAC is also supported by the D30 but the documentation doesn't say?

Sure seems that way

 

[Deleted member 18309]

Sure seems that way

Odd. You’d think they’d mention that since many people use AAC. Especially iPhone users who don’t yet have stuff like LDAC and aptX support for iOS as far as I know.

 

[Deleted member 18309]

I did some research, and it seems that the preamp on this DAC has a volume range of 0-60, with a maximum output of 3V RMS. For those who are more technically inclined, do you have any idea whether the higher-than-usual output voltage will lead to me having limited volume play? My power amp has 1V RMS input sensitivity.

For reference, I use my Topping E30 preamp (2V RMS maximum output) at around -50db for moderate listening and sometimes go to -35db for louder listening.

 

[peterwen]

 

[AnalogSteph]

I did some research, and it seems that the preamp on this DAC has a volume range of 0-60, with a maximum output of 3V RMS. For those who are more technically inclined, do you have any idea whether the higher-than-usual output voltage will lead to me having limited volume play? My power amp has 1V RMS input sensitivity.

I don't know where you got the 3 V from, Amir got ~2.3 V on the line-out that you are likely to be using. 2 V to 3 V only is about 4 dB, so no biggie either way.

 

[Deleted member 18309]

I don't know where you got the 3 V from, Amir got ~2.3 V on the line-out that you are likely to be using. 2 V to 3 V only is about 4 dB, so no biggie either way.

It's on their spec sheet as well as their manual (https://drive.google.com/file/d/1pzRkCWQHgYrkyqNtWKqxne7w6rMJZyY9/view). Fixed output mode is indeed 2.2V but their preamp mode goes even higher than that. See clip of spec sheet in pic below ("Output level").

Regardless, thanks. I thought maybe 2V to 3V would be a massive difference in volume and thus wouldn't give me a lot of volume play.

 

[ninetylol]

It's on their spec sheet as well as their manual (https://drive.google.com/file/d/1pzRkCWQHgYrkyqNtWKqxne7w6rMJZyY9/view). Fixed output mode is indeed 2.2V but their preamp mode goes even higher than that. See clip of spec sheet in pic below ("Output level").

Regardless, thanks. I thought maybe 2V to 3V would be a massive difference in volume and thus wouldn't give me a lot of volume play.

I dont understand your question. You got 60 Steps of DAC Volume and your power amp to play with volume. What are you afraid of?

 

[Deleted member 18309]

I dont understand your question. You got 60 Steps of DAC Volume and your power amp to play with volume. What are you afraid of?

My power amp doesn't have a volume knob (but does have input gain adjustment for each channel, which I would like to avoid using unless really necessary). My concern was that, if I were to use the D30 as a preamp, 3V output is too large and thus increasing to low volumes on the pre of the D30 (e.g 10-20) would result in music being too loud. And hence I don't get a lot of opportunity to do fine volume adjustments. This already happened to me when I tried to use my Asgard as a preamp on low gain - I couldn't get the volume control past 9-10 o'clock.

 

[ninetylol]

Mh im no professional but wouldnt a power amp with a max input of 1Vrms and no volume control be pretty much obselete for its own category?

On the other hand since volume is logarithmic (3db more=2times the voltage or 10db more volume = 10 times the voltage) you should still have a lot of headroom to play with since volume of 50 is a bit quieter than fixed mode = 2.2 Vrms. A volume of 40 would probably be about 1Vrms.

 

[odyo]

This is quite nice. Give or take same dac as e30, the rest is extra for only $30

 

[Deleted member 18309]

Mh im no professional but wouldnt a power amp with a max input of 1Vrms and no volume control be pretty much obselete for its own category?

My power amp is vintage, haha. Denon POA-800, supposedly manufactured around 1986-1991. I don't know how sensitive inputs are for modern power amps which don't have volume control, but I did read that 1V sensitivity isnt unusual. According to manual, IOTAVX PA3 (modern class AB without volume control) has input sensitivity of 0.2V and "input overload" of 4V. Not an expert either and not 100% clear what it means, but it seems more sensitive than my power amp?

On the other hand since volume is logarithmic (3db more=2times the voltage or 10db more volume = 10 times the voltage) you should still have a lot of headroom to play with since volume of 50 is a bit quieter than fixed mode = 2.2 Vrms. A volume of 40 would probably be about 1Vrms.

Ah, this was the part I was confused about. I wasn't clear whether digital volume controls are still logarithmic like analogue ones. If what you say is correct (and it sounds like it's correct - a linear volume control would be quite strange) then I reckon there's nothing to be too concerned about. Thanks for that.

 

[cheesyjimmy]

How does this compare to the Fiio K5 Pro? I'm looking for an affordable all-in-one solution for my DT990s 250 Ohm.